Mahmoud K Z, Hijazi A A
Department of Animal Production, Jordan University of Science and Technology, Irbid, Jordan.
J Anim Physiol Anim Nutr (Berl). 2007 Aug;91(7-8):333-40. doi: 10.1111/j.1439-0396.2006.00659.x.
This study was conducted to investigate the effect of vitamin A and E supplementation on the antioxidant defences of broiler chickens against carbon tetrachloride (CCl(4))-induced oxidative stress at 4 weeks of age. Superoxide dismutase (SOD) and glutathione peroxidase (GPX) activities as well as total antioxidant (TAO) level were analysed before and after CCl(4) challenge. Day-old Lohman broiler chickens (n = 144) were randomly assigned to six factorially arranged dietary treatments consisting of vitamin A [1.35 (control) or +20 mg/kg] and vitamin E [20 (control), +40 or +60 mg/kg]. The background of vitamins A and E in the basal diet was 4500 IU (1.35 mg) and 30 IU (20 mg) respectively. At 4 weeks of age, eight chickens from each treatment were bled before interperitoneal injection with 1 ml of CCl(4) (mixed with olive oil in a ratio of 1:1) and bled again 24 h post-injection. Vitamin E supplementation decreased (p < 0.05) the activity of both SOD and GPX and showed a tendency (p = 0.07) for TAO reduction. CCl(4) attenuated SOD and GPX activities as well as TAO level. The decrease was profound (p < 0.05) in chickens fed the basal diet as well as those fed basal diet supplemented with 20 mg vitamin A. TAO levels behaved similarly when chickens were challenged with CCl(4). After CCl(4) injection, SOD activities of all experimental groups were equivalent. The presence of vitamin A decreased (p < 0.05) plasma GPX activity in chickens fed the basal diet supplemented with 40 mg/kg of vitamin E. Results of this experiment suggested that vitamin E supplementation elevated antioxidant enzyme activities while vitamin A supplementation attenuated this effect. Vitamin E supplementation improved the total reducing power by maintaining comparable levels of TAO upon CCl(4) challenge. Further experiments need to be carried out to investigate the role of vitamin A in oxidative stress and to evaluate the lipid peroxidation products.
本研究旨在调查补充维生素A和E对4周龄肉鸡抗氧化防御能力的影响，以抵抗四氯化碳（CCl₄）诱导的氧化应激。在CCl₄攻击前后分析了超氧化物歧化酶（SOD）和谷胱甘肽过氧化物酶（GPX）的活性以及总抗氧化剂（TAO）水平。将1日龄的罗曼肉鸡（n = 144）随机分配到六种析因设计的日粮处理组，这些处理组由维生素A [1.35（对照）或 +20 mg/kg] 和维生素E [20（对照）、+40或 +60 mg/kg] 组成。基础日粮中维生素A和E的含量分别为4500 IU（1.35 mg）和30 IU（20 mg）。在4周龄时，每组处理的八只鸡在腹腔注射1 ml CCl₄（与橄榄油按1:1比例混合）之前采血，并在注射后24小时再次采血。补充维生素E降低了（p < 0.05）SOD和GPX的活性，并显示出TAO降低的趋势（p = 0.07）。CCl₄减弱了SOD和GPX的活性以及TAO水平。在饲喂基础日粮以及饲喂添加20 mg维生素A的基础日粮的鸡中，这种降低是显著的（p < 0.05）。当鸡受到CCl₄攻击时，TAO水平表现相似。注射CCl₄后，所有实验组的SOD活性相当。在饲喂添加40 mg/kg维生素E的基础日粮的鸡中，维生素A的存在降低了（p < 0.05）血浆GPX活性。本实验结果表明，补充维生素E提高了抗氧化酶活性，而补充维生素A减弱了这种作用。补充维生素E通过在CCl₄攻击时维持相当水平的TAO提高了总还原能力。需要进行进一步的实验来研究维生素A在氧化应激中的作用，并评估脂质过氧化产物。
